Clicking on empty space on tab bar activates window, but does not activate current terminal

### Windows Terminal version

1.12.10982.0

### Windows build number

10.0.19044.1645

### Other Software

_No response_

### Steps to reproduce

1. Open terminal.
2. activate some other window
3. click in terminal window at the empty space on tab bar
4. type with keyboard

### Expected Behavior

Typed characters show up in currently active terminal on terminal window.

### Actual Behavior

Nothing happens. Characters to not appear on active terminal.

Reproduce the four steps in the issue and inspect the tab-bar empty-space click and focus-handling entry points. Done means that after clicking empty space on the tab bar, typed characters appear in the currently active terminal.

Written by the indexing model from the issue text.